A New Adaptive Hardware Tree-Based Multicast Routing in K-Ary N-Cubes

ÐMulticast communication is a key issue in almost all applications that run on any parallel architecture and, hence, efficient implementation of of multicast is critical to the performance of multiprocessor machines. Multicast is implemented in parallel architectures either via software or via hardware. Software-based approaches for implementing multicast can result in high message latencies, while hardware-based schemes can greatly improve performance. Deadlock freedom in multicast communication is much more difficult to achieve resulting in more involved routing algorithms and higher startup delays. Hardware tree-based algorithms do not require these high startup delays, but do suffer from high probabilities of message blocking leading to poor performance. In this paper, we propose a new hardware tree-based routing algorithm (HTA) for multicast communication under virtual cut-through switching in k-ary n-cubes that outperforms existing software and hardware path-based multicast routing schemes. Simulation results are compared against several commonly used multicast routing algorithms and show that HTA performs extremely well under many different conditions. Index TermsÐMulticast communication, path-based routing, tree-based routing, deterministic routing, adaptive routing, virtual cut-through switching.